On Fri, Feb 25, 2011 at 11:36:39PM +0100, WanMil wrote:
But I also found out that some polygons that crosses the tile border which are closed in the OSM data are not neccessarily closed in the tiles. This has to be investigated. Does the splitter ensure that all closed ways in the OSM dump are also closed in the splitted tiles?
Could mkgmap be aware of the tile borders when closing polygons? When the open endpoints are within the current tile, do not close the polygon, and possibly emit a complaint to the error log. When the endpoints are outside the current tile borders, close by adding lines along the tile borders?
That should be no problem.
On a somewhat related note, there is some natural=coastline problem in Finland that JOSM cannot find in the natural=coastline extract of finland.osm.pbf. The error message only mentions generated relation and way IDs:
63240006: 2916352,960000 to 3014656,1474560 # : 62.578125,20.599365 to 64.687500,31.640625
2011/02/26 11:13:04 WARNING (MultiPolygonRelation): 63240006.osm.gz: Multipolygon http://www.openstreetmap.org/browse/relation/4611686018427480001 contains errors. 2011/02/26 11:13:04 WARNING (MultiPolygonRelation): 63240006.osm.gz: Polygon 4611686018427486852(8P)(4611686018427483429[8P]) carries role inner but lies inside an inner polygon. Potentially its role should be outer.
It would be helpful to see a coordinate of one of the ways. I guess that this is being caused by two islands being on top of each other. Apparently, JOSM could only catch that if the coastlines intersected.
Ok, sounds good as a first solution. I'll post a patch.
Marko